Shelley Duvall is best known for her star turn opposite Jack Nicholson in The Shining, Robin Williams in Popeye, and many other films from the ’70s and early ’80s. But the once in-demand actress has been living a radically different life since leaving the spotlight and has been grappling with a serious mental illness, according to a shocking preview clip of her upcoming appearance on Dr. Phil, for an episode set to air Friday, November 18.

The startling clip, which you can watch above, released Tuesday, November 16, shows talk show host Phil McGraw questioning the actress, 67, who claims that her late costar Robin Williams has become a shape-shifter, that she’s being threatened by a fictional Robin Hood character and that she worries she has a disc implanted in her body.

Among her disturbing comments, Duvall — who is almost unrecognizable since her heyday — tells the talk show host, 66, she doesn’t believe Williams is “really dead,” and instead is convinced he’s “shape-shifting.”

“Do you see him?” asks Dr. Phil.

“Have, yes,” the former Popeye actress says.

Duvall also tells Dr. Phil: “The man who’s threatening me is the Sheriff of Nottingham.”

At another point, she claims: “I think there’s a worrying disc inside me,” lifting up her pant leg to indicate she believes she has an implant under her skin.

“I’m very sick. I need help,” she tells Dr. Phil.

Watch the shocking preview for the episode above.

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